English Heritage and is now in the collection of the Durham University Museum of Archaeology. The wall at Milecastle 19 was less than wide, with a noticeable stepped reduction in wall thickness just east of the milecastle. This step occurred between the second and third courses and is thought to indicate a later repair of the wall. A causeway used to be visible across the vallum to the south of the milecastle. An English Heritage report in the late 1990s found that MC19 was one of only two milecastles being actively damaged by agriculture (the other being Milecastle 9) and that it had almost totally been destroyed through farming. Associated turrets Each milecastle on Hadrian's Wall had two associated turret structures. These turrets were positioned approximately one-third and two-thirds of a Roman mile to the west of the Milecastle, and would probably have been manned by part of the milecastle's garrison. The turrets associated with Milecastle 19 are known as Turret 19A and Turret 19B. Turret 19A Turret 19A (East Clarewood) lies beneath the modern Military Road, though of rough stone walling, high, remains visible within a hedge. The door was thought to lie at the western end of the turret's south wall. The turret was apparently dismantled by the Romans, with the latest evidence of occupation being some pottery of 200 AD. It was examined by Birley in 1932, who found pottery dating only to the 2nd century AD, and found to be of the same construction as Turrets 18A and B except that the recess was blocked up with walls founded on earlier occupation earth. A doorjamb and hypocaust pillar were found to have been incorporated into the wall. Irregularities in the vallum to the south of Turret 19A were once visible, consisting of gaps in the southern mound that were protected by an additional mound outside of the line in the manner of a traverse. Turret 19A was scheduled as an ancient monument at the same time as the milecastle. Location on Ordnance Survey 1:25 000 map: Turret 19B Turret 19B (West Clarewood) also lies beneath the modern Military Road, with no visible remains, and was excavated in 1932. This turret was constructed mainly with clay rather than mortar and has wider walls than normally found on narrow wall turrets, being thick. The door was proven to lie at the western end of the south wall and